Brake mechanism



May 8, 923.

H. VANDERBEEK BRAKE MECHANISM Filed July 1921 Patented May 8, 1923.

UNITED STATES P TENT genes. 1

HERBERT vmnnmsnnxgor na'rnorr OHIO.

nn'raorr, mcznosn, hssrelvonl To his rmxnn ma comm, or nn'raorr, moment, A oonroaurron or.

v BRAKE uncnnus'u.

. Application filed July 8,

To all whom it may concern.

H Be it known that I, Hs'nnnnr Vannsmsnnn,

a citizen of the United States, and a resident of the'city of Detroit ln-the county of 5 )Vayne and State of Michigan, have invented a new and useful Improvement in Brake Mechanism, of whichthe following is a specification. y ,This invention relates principally to brake mechanisms of the externalcontracting friction band type particularly adapted for use in connection with wheels of motor vehicles. One of the principal objects of the resent invention is to rovide a s'imp'lean elficient means-for ad1ustin the-brake band to take up wear of the bra elining'and tosecure a uniform clearance between said lining and the brake drum. =Another object is to rovide separate means for adjusting'each u alf of the brake band, whereby one of said halves may be adjusted without disturbin the adjustment of the other half.'- Other objects are to provide for simplicity and cheapness of construction and to obtain other advantages. 1

1 The invention consists I principally in the improved means for ad uSting the brake band; and :it also consists in the combinations and arrangements of parts hereinafter described.

In the accompanying drawing, which forms part of this specification, and where,' in like numerals refer, to like parts wherever they occur,

Pig. 1 is a vertical crossscction through a brake drum. a brake mechanism embodying my invention being shown in connection therewith. the brake being: shown in released position; and.

F ig. 2 is a fragmentary cross-section simi lar to Fig. 1 showing the broke in applied position: 7

--:Tl1e brake mechanism shown in the accompanying drawing comprises a brake drum 3 adapted 10 LE secured to tho rear wheel-{not shown) of tin motor vehicle. The brake drum i. prov ded with l pc'riph ersix rim or brake tinny}; t. which is cncircled hv an external hand brake compris- QQ ng a split semi-flexib e metallic band 5 hav- 1881. Berk] I 'o. m ni.

ing a suitable brake lining material 6. The brake lining 6 is rivebedo otherwise secured to the inner surface of't e metallic band '5 and! is adapted to 'frictioimlly engage the outer bra g surface of the brake flange! of the brake drum. Thebrake band 5 is held from rotating with the brake drum by means of an anchor bracket 7, which is-riveted to the inner face of a stationary brake diskpr dust guard 8. This brake disk 8 closes the openend of the brake drmn'and-is adapted to be rigidly secured to the stationary axle -hous1ng.(not shown) i The brake druin and the stationary brake shield 8 are provided, re's tively, 05 with axially alined central ci'rcu ar openin s 9-and l0, thropgh which project the ax e housing and the wheel hub, respectively.

The anchor bracket 7-is secured to'the brake shield Bat a point diametrically op- 10 posite to the opening in the brakeband and is provided. with an anchor stud 11, having a squared end portion which projects into the channeled portion 12 of a center fitting 13. The center fitting 13 is riveted or otherwise rigidl secured to the outer surface of the brake hand midwa between the" ends thereof. The channel portion 12 of the center fitting 13 of the-brake band is closed by said bridge band and is of a depth'suflicient to permit slight movement of said fitting towards and "away from theaxis of the brake drum when said bandis contmctcd and expanded.

The brake band is contracted to bring the lining .material thereof into frictional engagement with the outer surface of thebrake ange by means of an operating mechanism which is operatively connected to the ends of said band. Said mechanism comprises; an end fittings or bracket members 14' and 15, which are rigidly secured to thercspective upper and lower e'nds of the brake band, and a bracket 18, which is rigidly securerl lo the stationary hrnke disk 8 adjacent to said and fittings. Thc'blfarkcl 1G is pro sided with an almtnwnt flange [7 that projects beyond the periphery of the brake drum and is slotted transversely to the axis of the brake drum, as at 18, to receive a stud 19.

The upper end portion of the stud 19 passes through a conical bore in an outwardly projecting lug portion 20 of the uppermost. end fitting l4; and the lower end portion of said stud passes through a transverse bore in a trunnion pin 21. The trunnion pin 21 has its end portions journaled in the spaced branches the bifurcated outer end portion of the lower arm 'of a bent operating lever 22. The free end of the lower arm of the operating lever 22 is pivotally secured to a -lug 23 on the lowermost end fitting by means of a pivot pin 24, which passes through alined holes in said lug and in the branches of the bifurcated portion of said lever. The usual pull rod 25 is pivotally connected to the free end of the upper arm of the operating lever and is extended forward for connection with a foot pedal or hand operating lever (not shown).

Sleeved on the stud 19, .above and below the abutment bracket 16,.are helical springs 26 and 27. The uppermost spring 26. which is of a larger diameter than the spring 27 and loosely surrounds the stud, is supported at its lower end on the upper surface of the abutment flange 17 of the bracket 16 with its upper end bearing against the under side of the lug 20 on the uppermost end fitting 14. The lowermost spring 27 is suported at its lower end on the upper surace of the trunnion pin 21. The upper end of the spring 27 cooperates with the under side of a shoulder or collar 28 formed integral with the stud 19 adjacent to the underside of the abutment flange 17.

The upper and lower ends of the stud 19 extend beyond the lug 20 of the uppermost end fitting 14 and the trunnion pin 21, respectively, and are threaded to receive winged nuts 29 and 30, respectively. The upper surface of the lug 20 of the uppermost end fitting 14 is rovided with convex portions 31 adapted to cooperate with concave depressions in the adjacent face of the ad'usting nut 29, whereby said nut is prevente from becoming loosened.

The lowermost adjusting nut 30 is also formedwith concave depressions, which cooperate with the under side of the trunnion pin 21 on opposite sides of the contracting stud 19 and prevent said nut from becoming loosened.

\Vhen it is desired to apply the brake, the brake pedal or lever is actuated to pull the pull rod 25 forward. thereby causing the operating lever 22 to fulcrum on the trunnion pin 21. This action causes the bifurcated end of the lower arm of the lever to swing upward and, by reason of the pivotal connection between said arm and the lower end of the brake band, force said end upward into engagement with the brake drum. This n ward movement of the lower end of the braie band draws the lower half half of the brake of said band tightly about the lower half of the brake drum. After the lower end of the brake band has engaged the drum, the fulcrum point of the operating lever is shifted from the trunnion pin 21 to the pivot pin 24, whereby a continued forward pull on said lever pulls down the contracting stud 19 and causes the up r half of the brake band to be drawn tig tly around the. upper half of the drum. The downward movement of 'the stud 19 causes the lowermost spring 27, together with the collar portion of said stud to move away from the abutment flan 17, while the downward movement of t e uppermost end fitting. 14 causes the uppermost spring 26 to be compressed between said bracket and said uppermost end fitting 14.

Upon release of the operating lever, the uppermost spring 26 forces the uppermost en fitting 14 upwardly, thereby releasing the upper half of the brake band from engagement with the brake drum. The pressure of the spring 26 againstthe uppermost end fitting 14, also causes the stud, together with the'trunnion pin 21, to move upwardly with said fitting, which action releases the lower half of the brake band from engagement with t e brake drum. This upward movement 0 the stud 19 and trunnion pin 21 continues until the collar portion 28 of said stud engages the abutment flange 17, thereb preventing further lifting o s stud y the lowermost spring 27. The lowermost 5 ring 27, which remains inacaid tive when he brake is applied, cooperates with the collar portion 28 of the stud 19 and the trunnion pin 21 to hold the pin 21 in engagement with the lowermost adjusting nut 30 and also to prevent movement of said pin with respect to said stud, except when the nut 30 IS manipulated to adjust the lower halfof the brake band.

With the arran ement described. either hand may be readil adjusted independently of the other ha f, to take up wear of the brake linin or to obtain an even amount of clearance tween both halves of the brake band and the braking the ends of said band for expanding and contracting the same a fixed member adjacent to said ends, and means associated with said fixed member and the end portions of said band for adjusting the clearance between one half of said band and said rotating element without disturbing the adjus ment of the other half of said band.

2. A rotary member, a circumferentially contractible split brake band encircling said member and adapted to frictionally engage the outer surface thereof, means for preventing rotation of said band, operating means operatively connected to the ends of said band for contracting and expanding the same into and out of en agement with said rotary member, and ad ustable means operatively connected to said operating means for regulating the clearance between one half of said band and said-rotary member independently of the other half of said (ill .dered portion, and a second; sprin band, said last mentioned means comprising a fixed portion with reference to which the adjustments are made for both halves.

3. A brake drum, an open external friction brake band arranged to cooperate therewith, a stationary abutment disposed opposite to the opening in said band, an operating lever pivotally connected to one end of said band, a stud having a slidable, connection with the other end of said band and a slidable and pivotal connection with said,

operating lever, a spring surrounding said stud with its ends abutting againstsaid abutment and said second ment oned end of said brake band, said stud having a shouL surrounding said stud between the shou dered portion thereof and said lever.

4. A brake drum, an openexternal' friction brake band arranged to cooperate therewith, a stationary abutment disposed opposite to the openin in said band, an operating lever pivotal y connected to one end of said band, a stud having a slidable connection with the other end of said band and a slidable and pivotal connection with said operating lever, a spring surrounding said stud with its ends abutting against said abutment and said second mentioned end portion of said brake band, said stud having a shouldered portion, a second 8 ring surrounding said stud between the s ouldered portion thereof and said lever, and

adjustable means on the ends of said stud cooperating with the second mentioned end portion of said band and said operating lever respectively for adjusting the clearance between said drum and said band.

5. A brake drum, an open external friction brake band arranged to cooperate therewith, a stationary abutment disposed opposite to the opening in said band, an operating lever pirotally connected to one end of said band, a stud having a slida-ble connection with the other end of said band and a slidable and pivotal connection with said operating lever,

a spring surroundin said stud with its ends abutting against sai abutment and the second mentioned end portion of said brake band respectively, said stud having an integral collar formed thereon, a second spring surrounding said stud between the collar thereof and said lever, said collar being adapted to cooperate with said abutment in the released position of said band, and adjustable' means on the ends of said stud cooperating with the second mentioned end portion of said brake band and operating ever respectively for adjusting the clearance between one half of said band and said groan independently of the other half of said an v 6. A brake drum, an open external friction brake band arranged to cooperate there with, brackets fixed to the respective ends of said band a stationary abutment located between said brackets, an operating lever pivoted to one of said end brackets and havmg a trunnion pin journaled therein, a stud passing through alined openings in the other of said, end bi'ackets,saidi abutment and said trunnion pin and having an inte ral collar, a. spring surrounding said stud with its ends abutting a inst said second mentioned bracket an ,said: abutment respectively, a second spring surroundin said stud between the collar thereof and sai trunnion pin, and nuts on the ends of said studs, said nuts. being adapted to engage respectively said trunnion in and the end bracket at the opposite encFof saidbandi 7. A brake drum, an open external fric-' tion brake band arranged to cooperate there with, an anchor for said band, a stationary abutment disposed between the ends of said band, an operating lever pivoted to one end of said band and having a trunnion pin journaled therein, a stud passing through an opening in said abutment and having an integral collar ortion located adjacent thereto, said stud iaving one end adjustably connected to said trunnion pin and having its other end adjustably connected to the opposite end of said band, a spring interposed between said abutment and-said last mentidned end of said band, and a second spring surrounding said stud between the collar thereof and said trunnion pin.

8. A brake drum, an 'open external brake band arranged to cooperate therewith, an f pin mounted therein, a stud passing through V alined openings in the other of said end brackets, said abutment and said trunnion pin, said stud having a collar formed thereon adapted to cooperate with said abutment in the released position of said brake. a spring surrounding said stud between one side of jecting end portions of said stud, whereby said abutment and said second mentioned the clearance between said band and said bracket, a second spring surroundin said drum may be regulated. stud between the collar thereof an said I Signed at Detroit, Michigan, this 29th trunnion pin, said stud grojecting beyond day of June, 1921.

said second mentioned racket and said trunnion pin, and adjusting nuts on the pro- HERBERT VANDERBEEK. 

